Admittedly, the actual exchange of sex for money is, as you say, not illegal in Ireland, but it's virtually impossible for a prostitute to work there without breaking some law or involving someone else in lawbreaking, because most activities associated with prostitution are illegal (operating a brothel or keeping any premises for the purpose of prostitution, advertising, and soliciting are all illegal, and anyone employed by prostitutes, as, say, a driver or to provide security is also breaking Irish law). Bangladesh appears to be similar, though perhaps with a few less such laws. Places which don't arm the police with plenty of excuses to harass prostitutes are quite rare.